Mouse LIF is a lymphoid factor that promotes long-term maintenance of the pluripotency of mouse embryonic stem cells by suppressing spontaneous differentiation1,2. Leukemia Inhibitory Factor (LIF) has additional functions such as cholinergic neuron differentiation, bone and fat metabolism, mitogenesis of certain factor dependent cell lines and promotion of megakaryocyte production in vivo. Mouse LIF is an approximate 20 kDa protein containing 202 amino acid residues.
Stemfactor LIF, Mouse Recombinant
Greater than 98% by SDS-PAGE analysis.
LIF is supplied as a 0.22 µm sterile filtered liquid in PBS containing 1% w/v BSA as carrier.
Storage and Stability
LIF is shipped at room temperature. Concentrated LIF is stable for up to 6 months from date of receipt when stored at 4 °C. Prior to use dilute LIF in sterile tissue culture media, aliquot to a convenient concentration, and store at 4 °C. Avoid freeze-thaw cycles as it can result in loss of activity.
Tested to be negative for mycoplasma by PCR and microbial contamination by a sterility test.
Less than 1 EU/µg of LIF as determined by the LAL method.
Mouse LIF activity is assessed by its ability to decrease the proliferation of M1 myeloid leukemia cells. The specific activity is 1×106 units/mL (Cat. No. 03-0011) and 1×107 units/mL (Cat. No. 03-0011-100), where 50 units is defined as the amount of mouse LIF required to decrease proliferation of M1 cells suspension by at least 50%.